Punch Wound Over the Fifth Metacarpal Head: To Suture or Not
A 24-year-old dishwasher punched a wall during an argument and presents 20 hours later with a 1.2 cm laceration over the dorsal aspect of the fifth metacarpal head. The edges are macerated, there is surrounding erythema with a small amount of purulent drainage, and he has full range of motion with intact sensation and capillary refill. Radiograph shows no fracture and no radiopaque foreign body. He has no allergies, takes no medications, and 'maybe' had a tetanus shot in high school. He is uninsured, and his employer requires a note before he can return to work. He asks you to 'just stitch it so I can work tomorrow.' The clinic has plain lidocaine, nylon suture, and oral antibiotics on site. Hand surgery is across town with no appointment until the morning.
1. Why is primary closure the wrong choice here, and what is your wound plan instead?
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This is a fight bite - a human bite over the metacarpophalangeal joint - even though the injury came from a wall, because the mechanism was a closed fist striking a hard surface with the knuckles.
- Anatomy: at the MCP joint the skin laceration sits directly over the extensor tendon and joint capsule. During the punch the soft tissue is driven proximally, so the tendon and joint can be inoculated even through a 1 cm skin wound. Tendon integrity and joint penetration cannot be reliably assessed in an urgent care exam room.
- Organisms: oral flora - Eikenella corrodens, viridans streptococci, anaerobes - plus skin staphylococci. Primary closure of a contaminated, 20-hour-old, already-draining wound traps them in a closed space.
Plan: field block with plain lidocaine (no epinephrine in the digit), copious irrigation with 500-1000 mL of saline, gentle debridement, no sutures, loose gauze dressing, splint in extension, elevation, oral antibiotics, hand surgery follow-up within 24 hours, and a wound check in 24 hours.
Return precautions: fever, red streaking, increasing pain, loss of motion, or numbness brings him back immediately. Document that closure was deliberately not performed and that he understood why.
2. Choose the antibiotic and settle the tetanus question, with your reasoning.
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Antibiotic: amoxicillin-clavulanate 875/125 mg PO twice daily for 5-7 days. That spectrum covers Eikenella, streptococci, oral anaerobes, and methicillin-susceptible staphylococci - which is exactly the human-bite spectrum. If he were penicillin-allergic, clindamycin 300-450 mg four times daily plus trimethoprim-sulfamethoxazole DS twice daily is a reasonable substitute. Do not use cephalexin alone; it misses Eikenella and anaerobes, which is the classic error in bite wounds.
Tetanus: this wound is tetanus-prone - dirty, more than 6 hours old, devitalized tissue, purulent drainage. His status is 'maybe,' which is functionally unknown. Give Tdap (or Td) now plus tetanus immune globulin 250 units IM at a separate site. If he had a documented complete primary series and a booster within 5 years, TIG would not be needed, but a high-school guess is not documentation. Ask about prior anaphylaxis to vaccine components before administering.
Note in the chart which product, dose, site, and date were given, and that a plan for the remaining series was provided.
3. Write the work note and the safety net, and explain what you will and will not disclose to the employer.
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The note: he works as a dishwasher - wet, chemically exposed, and physically repetitive. There is no safe 'light duty' version of dishwashing with an open hand wound.
Seen [date]. Open wound of the right hand, splinted, on antibiotics, referred to hand surgery. No work until cleared by hand surgery. Restrictions: no use of the right hand, no immersion in water, keep the dressing dry and intact, elevate the hand when resting.
Give him the original and send a copy to the employer only with his written authorization. Workers' compensation may pay for the visit, but the note should still contain the minimum necessary information - diagnosis, restrictions, and expected duration, not the mechanism or the full history.
Safety net: written return precautions, the hand surgery appointment time and phone number, a 24-hour wound check in your clinic, and explicit instruction to go to the ED for fever, red streaking up the arm, or inability to move the fingers. Confirm he has a way to fill the prescription and a way to get to hand surgery, and document both the instructions given and his teach-back.